Fix missing dependencies for BT AVRCP tests

Currently `apparmor-bluez-avrcp-volume` test request to run
`bluez-avrcp-volume` test, allowing to install all dependencies for both
tests. Running solely one test ends up in errors due to missing
dependencies.

Signed-off-by: Frédéric Danis <frederic.danis@collabora.com>

test-cases/apparmor-bluez-avrcp-volume.yaml

@@ -17,6 +17,7 @@ metadata:
 
   macro_install_packages_preconditions: chaiwala-tests
                                         apertis-tests-apparmor-report
+                                        python3-dbus python3-gi
 
   pre-conditions:
     - "Please note that connman disables bluetooth by default on a fresh image.

test-cases/bluez-avrcp-volume.yaml

@@ -21,6 +21,7 @@ metadata:
        to have headphones or a speaker plugged into the Apertis device."
 
   macro_install_packages_preconditions: apertis-tests python3-dbus python3-gi 
+                                        chaiwala-tests
 
   expected:
     - "If success, the following output should be generated by btmon:"